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1.
Chemosphere ; 286(Pt 2): 131682, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34358895

RESUMO

The ultraviolet (UV)-based advanced oxidation process (AOP) is a powerful technology for removing pathogenic microorganisms and contaminants of emerging concern (CECs) from water. AOP in potable water reuse has been predominantly based on traditional low-pressure mercury (LP-Hg) lamps at 254 nm wavelength, supplemented by hydrogen peroxide addition. In this review, we assessed the potential of unconventional UV wavelengths (UV-B, 280-315 nm and UV-C, 100-280 nm) compared to conventional one (254 nm) in achieving the attenuation of pathogens and CECs. At the same UV doses, conventional 254 nm LP-Hg lamps and other sources such as, 222 nm KrCl lamps and 265 nm UV-LEDs, showed similar disinfection capability for viruses, protozoa, and bacteria, and the effect of hydrogen peroxide (H2O2) addition on disinfection remained unclear. The attenuation levels of key CECs in potable water reuse (N-nitrosodimethylamine and 1,4-dioxane) by 185 + 254 nm LP-Hg or 222 nm KrCl lamps were generally greater than those by conventional 254 nm LP-Hg and other UV lamps. CEC degradation was generally enhanced by H2O2 addition. Overall, our review suggests that 222 nm KrCl or 185 + 254 nm LP-Hg lamps with the addition of H2O2 would be the best alternative to conventional 254 nm LP-Hg lamps for achieving target removal levels of both pathogens and CECs in potable water reuse.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Dimetilnitrosamina , Dioxanos , Peróxido de Hidrogênio
2.
Life Sci Alliance ; 5(1)2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34764206

RESUMO

Understanding pathways that might impact coronavirus disease 2019 (COVID-19) manifestations and disease outcomes is necessary for better disease management and for therapeutic development. Here, we analyzed alterations in sphingolipid (SL) levels upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 infection induced elevation of SL levels in both cells and sera of infected mice. A significant increase in glycosphingolipid levels was induced early post SARS-CoV-2 infection, which was essential for viral replication. This elevation could be reversed by treatment with glucosylceramide synthase inhibitors. Levels of sphinganine, sphingosine, GA1, and GM3 were significantly increased in both cells and the murine model upon SARS-CoV-2 infection. The potential involvement of SLs in COVID-19 pathology is discussed.


Assuntos
COVID-19/metabolismo , Modelos Animais de Doenças , Esfingolipídeos/metabolismo , Replicação Viral/fisiologia , Animais , COVID-19/prevenção & controle , COVID-19/virologia , Chlorocebus aethiops , Cromatografia Líquida/métodos , Dioxanos/farmacologia , Gangliosídeos/sangue , Gangliosídeos/metabolismo , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/metabolismo , Humanos , Espectrometria de Massas/métodos , Camundongos Transgênicos , Pirrolidinas/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Esfingolipídeos/sangue , Esfingosina/análogos & derivados , Esfingosina/sangue , Esfingosina/metabolismo , Células Vero , Replicação Viral/efeitos dos fármacos
3.
Int J Mol Sci ; 22(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34638775

RESUMO

Biodegradation of 1,4-dioxane (dioxane) contamination has gained much attention for decades. In our previous work, we isolated a highly efficient dioxane degrader, Xanthobacter sp. YN2, but the underlying mechanisms of its extraordinary degradation performance remained unresolved. In this study, we performed a comparative transcriptome analysis of YN2 grown on dioxane and citrate to elucidate its genetic degradation mechanism and investigated the transcriptomes of different dioxane degradation stages (T0, T24, T48). We also analyzed the transcriptional response of YN2 over time during which the carbon source switched from citrate to dioxane. The results indicate that strain YN2 was a methylotroph, which provides YN2 a major advantage as a pollutant degrader. A large number of genes involved in dioxane metabolism were constitutively expressed prior to dioxane exposure. Multiple genes related to the catabolism of each intermediate were upregulated by treatment in response to dioxane. Glyoxylate metabolism was essential during dioxane degradation by YN2, and the key intermediate glyoxylate was metabolized through three routes: glyoxylate carboligase pathway, malate synthase pathway, and anaplerotic ethylmalonyl-CoA pathway. Genes related to quorum sensing and transporters were significantly upregulated during the early stages of degradation (T0, T24) prior to dioxane depletion, while the expression of genes encoding two-component systems was significantly increased at late degradation stages (T48) when total organic carbon in the culture was exhausted. This study is the first to report the participation of genes encoding glyoxalase, as well as methylotrophic genes xoxF and mox, in dioxane metabolism. The present study reveals multiple genetic and transcriptional strategies used by YN2 to rapidly increase biomass during growth on dioxane, achieve high degradation efficiency and tolerance, and adapt to dioxane exposure quickly, which provides useful information regarding the molecular basis for efficient dioxane biodegradation.


Assuntos
Adaptação Fisiológica , Biomassa , Dioxanos/metabolismo , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Xanthobacter/metabolismo , Xanthobacter/genética
4.
Int J Oral Maxillofac Implants ; 36(5): 1024-1031, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34698730

RESUMO

PURPOSE: To describe the postoperative complications following lateral wall sinus augmentation using (poly L-lactideco-ε-caprolactone; PLCL) and natural polysaccharides polymers-coated bovine bone (PBB). The secondary aims were to examine histologic findings and to propose complication management alternatives. MATERIALS AND METHODS: This retrospective study included 61 subjects who underwent 67 lateral wall sinus augmentation procedures using PBB in the standard protocol. In cases that presented complications, treatment included additional antibiotic therapy, implant removal, or sinus reentry and total removal of the grafting material. In three cases, biopsy specimens were taken from the sinuses, and histologic analyses were performed. RESULTS: The prevalence of postoperative complications was 32.8% (22 of 67 cases) in 18 of the patients (29.5%). The most prevalent symptoms were persistent pain (68.2%), swelling (63.6%), and oroantral fistula (54.5%). Radiographic signs appeared in 45.5% of the complications. A total of 24 implants failed; thus, an overall 80.3% survival rate was established at 19 months. The vast majority of complications (86.4%) were treated eventually with reentry surgery and revealed that the sinus was full with granulation tissue surrounding pieces of a nonossified rubber-like material. In cases where implants were placed, nonosseointegrated implants were surrounded by soft tissue. The sinus was cleaned thoroughly; the graft material remnants were removed together with inflamed parts of the sinus membrane, followed by chlorhexidine and saline lavages. In the biopsy specimens taken from the sinus cavity, there were no histologic features of new bone formation around the grafted material. CONCLUSION: Lateral wall maxillary sinus augmentation using PBB was associated with an acute sinus infection histologic appearance and with a 7-times-higher failure rate compared with previous reports. This serious adverse event suggests that PBB cannot be recommended for maxillary sinus augmentations.


Assuntos
Substitutos Ósseos , Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Animais , Substitutos Ósseos/efeitos adversos , Transplante Ósseo , Caproatos , Bovinos , Implantação Dentária Endo-Óssea/efeitos adversos , Implantes Dentários/efeitos adversos , Dioxanos , Humanos , Lactonas , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Estudos Retrospectivos , Levantamento do Assoalho do Seio Maxilar/efeitos adversos
5.
Int J Mol Sci ; 22(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34638879

RESUMO

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers in humans. At early stages CRC is treated by surgery and at advanced stages combined with chemotherapy. We examined here the potential effect of glucosylceramide synthase (GCS)-inhibition on CRC biology. GCS is the rate-limiting enzyme in the glycosphingolipid (GSL)-biosynthesis pathway and overexpressed in many human tumors. We suppressed GSL-biosynthesis using the GCS inhibitor Genz-123346 (Genz), NB-DNJ (Miglustat) or by genetic targeting of the GCS-encoding gene UDP-glucose-ceramide-glucosyltransferase- (UGCG). GCS-inhibition or GSL-depletion led to a marked arrest of the cell cycle in Lovo cells. UGCG silencing strongly also inhibited tumor spheroid growth in Lovo cells and moderately in HCT116 cells. MS/MS analysis demonstrated markedly elevated levels of sphingomyelin (SM) and phosphatidylcholine (PC) that occurred in a Genz-concentration dependent manner. Ultrastructural analysis of Genz-treated cells indicated multi-lamellar lipid storage in vesicular compartments. In mice, Genz lowered the incidence of experimentally induced colorectal tumors and in particular the growth of colorectal adenomas. These results highlight the potential for GCS-based inhibition in the treatment of CRC.


Assuntos
Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo , Dioxanos/farmacologia , Glicoesfingolipídeos , Pirrolidinas/farmacologia , Esferoides Celulares , Animais , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/metabolismo , Glicoesfingolipídeos/biossíntese , Glicoesfingolipídeos/genética , Células HCT116 , Humanos , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia
6.
Mater Sci Eng C Mater Biol Appl ; 128: 112299, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474850

RESUMO

A novel airflow shearing method was introduced to prepare microspheres efficiently with precisely control of microsphere size and homogeneity. The effects of technical parameters in the formation of the microspheres, such as solution concentration, nozzle size and airflow strength, were investigated. By optimizing the technical parameters (8% PLGA concentration, 27-32 G nozzle size, 6-8 l/min airflow strength), nano-hydroxyapatite and poly(lactide-co-glycolide) nanocomposite (nHA/PLGA) microspheres with a diameter around 250 µm and up to 40 wt% nHA content was prepared successfully. Especially, the microspheres possessed revealed great homogeneity and unique "acorn" appearance with two sides: A hard smooth side as well as a crumpled rough side, generated in the preparation process. Furthermore, the nHA/PLGA microspheres' potential application in bone tissue engineering was studied. In vitro, enhanced proliferation and osteogenic differentiation of the MC3T3-E1 cells was observed on as-prepared nHA/PLGA microspheres with high nHA content. In vivo, the BV/TV value of the microspheres with 20 wt% nHA was up to 75% and similar to the clinical products' performance. Moreover, beside high nHA content, the rough porous surface leads to bone ingrowth, which plays an important role in accelerating bone repair. Therefore, airflow shearing method could be an effective approach to fabricate biocompatible microsphere, and the as-prepared microspheres showed unique surface state and bone repair ability and making them as potential candidates for bone tissue engineering and bone implantation clinical applications.


Assuntos
Durapatita , Nanocompostos , Células Cultivadas , Dioxanos , Ácido Láctico , Microesferas , Osteogênese , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
7.
Biomacromolecules ; 22(9): 3873-3883, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34510908

RESUMO

The stereolithography process is a powerful additive manufacturing technology to fabricate scaffolds for regenerative medicine. Nevertheless, the quest for versatile inks allowing one to produce scaffolds with controlled properties is still unsatisfied. In this original article, we tackle this bottleneck by synthesizing a panel of photoprocessable hybrid copolymers composed of gelatin-graft-poly(trimethylene carbonate)s (Gel-g-PTMCn). We demonstrated that by changing the length of PTMC blocks grafted from gelatin, it is possible to tailor the final properties of the photofabricated objects. We reported here on the synthesis of Gel-g-PTMCn with various lengths of PTMC blocks grafted from gelatin using hydroxy and amino side groups of the constitutive amino acids. Then, the characterization of the resulting hybrid copolymers was fully investigated by quantitative NMR spectroscopy before rendering them photosensitive by methacrylation of the PTMC terminal groups. Homogeneous composition of the photocrosslinked hybrid polymers was demonstrated by EDX spectroscopy and electronic microscopy. To unravel the individual contribution of the PTMC moiety on the hybrid copolymer behavior, water absorption, contact angle measurements, and degradation studies were undertaken. Interestingly, the photocrosslinked materials immersed in water were examined using tensile experiments and displayed a large panel of behavior from hydrogel to elastomer-like depending on the PTMC/gel ratio. Moreover, the absence of cytotoxicity was conducted following the ISO 10993 assay. As a proof of concept, 3D porous objects were successfully fabricated using stereolithography. Those results validate the great potential of this panel of inks for tissue engineering and regenerative medicine.


Assuntos
Estereolitografia , Engenharia Tecidual , Dioxanos , Gelatina , Polímeros , Tecidos Suporte
8.
Phytother Res ; 35(10): 5899-5918, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34585447

RESUMO

A safer and more effective combination strategy designed to enhance the efficacy and minimize the toxicity of cisplatin in osteosarcoma (OS) is urgently needed. Zeylenone (zey), a cyclohexene oxide compound, exerted an obvious inhibitory effect on several cancer cell lines and exhibited little cytotoxicity towards normal cells, enabling zey to play a unique role in combination therapy. Thus, the study aimed to determine whether the combination of zey and cisplatin produces synergistic antitumour effects on OS and to further explore molecular mechanisms. Initially, we found that zey potentiated the anti-osteosarcoma efficacy of cisplatin and exhibited synergistic interactions with cisplatin in vitro, which also were confirmed in vivo by using xenograft model. Mechanistically, zey and cisplatin synergistically induced DNA damage, cell cycle arrest, necrosis, and apoptosis in OS cells. Importantly, zey had a high binding affinity for Hsp90 and reduced the expression of Hsp90, which further induced the suppression of AKT/GSK3ß signalling axis and the degradation of Fanconi anaemia (FA) pathway proteins. Thus, the Hsp90/AKT/GSK3ß and FA pathway are the key to the synergism between zey and cisplatin. Overall, zey shows promise for development as a cisplatin chemosensitizer with clinical utility in restoring cisplatin sensitivity of cancer cells.


Assuntos
Antineoplásicos , Neoplasias Ósseas , Anemia de Fanconi , Osteossarcoma , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Neoplasias Ósseas/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Cicloexanos , Dano ao DNA , Dioxanos , Glicogênio Sintase Quinase 3 beta , Humanos , Necrose , Osteossarcoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt
9.
J Wound Care ; 30(8): 626-630, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34382853

RESUMO

OBJECTIVE: The type of suture material affects the quality of scars. The aim of this study was to find the superior suture material for reduction mammoplasty between Prolene and Monocryl based on the comparison of scars. METHOD: A prospective observational study was conducted at a university-based hospital in Mashhad, Iran between October 2015 and September 2017. Monocryl and Prolene suture materials, used for closing the outermost layer in mammoplasty, were compared. Patients' incision scars were assessed objectively according to the Patient and Observer Scar Assessment (POSAS) criteria. The relevant CONSORT guideline was used for reporting this study. RESULTS: Seventy-eight women with a mean age of 36.8±9.5 years were entered into the study. The frequency of wound healing in both groups was 97.4% 1 month after surgery and by the third visit, 3 months after surgery, only one patient had a stretched scar. Moreover, wound inflammation in the first two visits was less frequent in the Prolene group that healed completely 3 months after surgery (after excluding the one patient with wide scar inflammation). The frequency of itching of the wound in the Monocryl group was 24.4%, 11.5% and 12.8% in the three follow-up visits, respectively, and the values for the Prolene group were 24.4%, 9.0% and 6.4%, respectively. No significant difference was seen between the two groups in terms of wound healing, inflammation and itching (p>0.05). Overall, 94.8% of patients were satisfied with the surgery. CONCLUSIONS: Our study revealed that there was no significant difference between Monocryl and Prolene. Hence, either of the two suture materials can be used for wound closure in reduction mammoplasty.


Assuntos
Mamoplastia , Ferida Cirúrgica , Adulto , Cicatriz/patologia , Dioxanos , Feminino , Humanos , Mamoplastia/efeitos adversos , Pessoa de Meia-Idade , Poliésteres , Polipropilenos , Técnicas de Sutura , Suturas
10.
ACS Appl Mater Interfaces ; 13(33): 38969-38978, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34399054

RESUMO

Controlling the microstructure of materials by means of phase separation is a versatile tool for optimizing material properties. Phase separation has been exploited to fabricate intricate microstructures in many fields including cell biology, tissue engineering, optics, and electronics. The aim of this study was to use phase separation to tailor the spatial location of drugs and thereby generate release profiles of drug payload over periods ranging from 1 week to months by exploiting different mechanisms: polymer degradation, polymer diluent dissolution, and control of microstructure. To achieve this, we used drop-on-demand inkjet three-dimensional (3D) printing. We predicted the microstructure resulting from phase separation using high-throughput screening combined with a model based on the Flory-Huggins interaction parameter and were able to show that drug release from 3D-printed objects can be predicted from observations based on single drops of mixtures. We demonstrated for the first time that inkjet 3D printing yields controllable phase separation using picoliter droplets of blended photoreactive oligomers/monomers. This new understanding gives us hierarchical compositional control, from droplet to device, allowing release to be "dialled up" without manipulation of device geometry. We exemplify this approach by fabricating a biodegradable, long-term, multiactive drug delivery subdermal implant ("polyimplant") for combination therapy and personalized treatment of coronary heart disease. This is an important advance for implants that need to be delivered by cannula, where the shape is highly constrained and thus the usual geometrical freedoms associated with 3D printing cannot be easily exploited, which brings a hitherto unseen level of understanding to emergent material properties of 3D printing.


Assuntos
Anti-Hipertensivos/química , Doença das Coronárias/tratamento farmacológico , Portadores de Fármacos/química , Excipientes/química , Indóis/química , Polímeros/química , Anti-Hipertensivos/farmacologia , Dioxanos/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Humanos , Indóis/farmacologia , Metacrilatos/química , Transição de Fase , Poliésteres/química , Impressão Tridimensional , Pirrolidinonas/química , Relação Estrutura-Atividade
11.
J Agric Food Chem ; 69(30): 8555-8564, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34286974

RESUMO

The dioxane lignin was isolated from extractives- and suberin-free cork (Quercus suber L.) by a modified acidolytic procedure and submitted to structural analysis by permanganate oxidation, analytical pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC-MS), liquid- and solid-state nuclear magnetic resonance (NMR) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. The molecular weight (Mw = 2500 Da) was assessed by size exclusion chromatography (SEC). The results obtained show that the cork lignin is of syringyl (S)/guaiacyl (G) type with a small proportion of p-hydroxyphenyl (H) units (S:G:H molar ratio of 23:72:5). Among a dozen detected lignin structures, those linked by ether bonds, such as ß-O-4' (38 mol %) and 4-O-5' (5 mol %), were the most abundant. The frequency of occurrence of ß-5', ß-ß', 5-5', tetrahydrofuran type, and structures arising from the condensation with concomitant procyanidins was assessed. Ferulates were the only cinnamic structure detected in the cork dioxane lignin.


Assuntos
Lignina , Quercus , Dioxanos , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34299106

RESUMO

Atherosclerosis involves an ongoing inflammatory response of the vascular endothelium and vessel wall of the aorta and vein. The pleiotropic effects of statins have been well described in many in vitro and in vivo studies, but these effects are difficult to achieve in clinical practice due to the low bioavailability of statins and their first-pass metabolism in the liver. The aim of this study was to test a vessel wall local drug delivery system (DDS) using PLA microstructures loaded with simvastatin. Wistar rats were fed high cholesterol chow as a model. The rat vessels were chemically injured by repeated injections of perivascular paclitaxel and 5-fluorouracil. The vessels were then cultured and treated by the injection of several concentrations of poly(L,L-lactide) microparticles loaded with the high local HMG-CoA inhibitor simvastatin (0.58 mg/kg) concentration (SVPLA). Histopathological examinations of the harvested vessels and vital organs after 24 h, 7 days and 4 weeks were performed. Microcirculation in mice as an additional test was performed to demonstrate the safety of this approach. A single dose of SVPLA microspheres with an average diameter of 6.4 µm and a drug concentration equal to 8.1% of particles limited the inflammatory reaction of the endothelium and vessel wall and had no influence on microcirculation in vivo or in vitro. A potent pleiotropic (anti-inflammatory) effect of simvastatin after local SVPLA administration was observed. Moreover, significant concentrations of free simvastatin were observed in the vessel wall (compared to the maximum serum level). In addition, it appeared that simvastatin, once locally administered as SVPLA particles, exerted potent pleiotropic effects on chemically injured vessels and presented anti-inflammatory action. Presumably, this effect was due to the high local concentrations of simvastatin. No local or systemic side effects were observed. This approach could be useful for local simvastatin DDSs when high, local drug concentrations are difficult to obtain, or systemic side effects are present.


Assuntos
Anti-Inflamatórios/farmacologia , Anticolesterolemiantes/farmacologia , Dioxanos/química , Sistemas de Liberação de Medicamentos , Inflamação/tratamento farmacológico , Sinvastatina/farmacologia , Animais , Anti-Inflamatórios/química , Anticolesterolemiantes/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , Ratos , Ratos Wistar , Sinvastatina/administração & dosagem
13.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298985

RESUMO

In this study, the temperature-dependent solubility of nicotinamide (niacin) was measured in six neat solvents and five aqueous-organic binary mixtures (methanol, 1,4-dioxane, acetonitrile, DMSO and DMF). It was discovered that the selected set of organic solvents offer all sorts of solvent effects, including co-solvent, synergistic, and anti-solvent features, enabling flexible tuning of niacin solubility. In addition, differential scanning calorimetry was used to characterize the fusion thermodynamics of nicotinamide. In particular, the heat capacity change upon melting was measured. The experimental data were interpreted by means of COSMO-RS-DARE (conductor-like screening model for realistic solvation-dimerization, aggregation, and reaction extension) for concentration dependent reactions. The solute-solute and solute-solvent intermolecular interactions were found to be significant in all of the studied systems, which was proven by the computed mutual affinity of the components at the saturated conditions. The values of the Gibbs free energies of pair formation were derived at an advanced level of theory (MP2), including corrections for electron correlation and zero point vibrational energy (ZPE). In all of the studied systems the self-association of nicotinamide was found to be a predominant intermolecular complex, irrespective of the temperature and composition of the binary system. The application of the COSMO-RS-DARE approach led to a perfect match between the computed and measured solubility data, by optimizing the parameter of intermolecular interactions.


Assuntos
Niacinamida/química , Termodinâmica , Acetonitrilas , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Dimerização , Dimetil Sulfóxido , Dimetilformamida , Dioxanos , Metanol , Modelos Químicos , Concentração Osmolar , Solubilidade , Soluções , Solventes , Espectrofotometria Infravermelho , Temperatura , Vibração , Água
14.
Sci Total Environ ; 794: 148690, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34198077

RESUMO

Co-contamination with chlorinated compounds and 1,4-dioxane has been reported at many sites. Recently, there has been an increased interest in bioremediation because of the potential to degrade multiple contaminants concurrently. Towards improving bioremediation efficacy, the current study examined laboratory microcosms (inoculated separately with two soils) to determine the phylotypes and functional genes associated with the biodegradation of two common co-contaminants (cis-dichloroethene [cDCE] and 1,4-dioxane). The impact of amending microcosms with lactate on cDCE and 1,4-dioxane biodegradation was also investigated. The presence of either lactate or cDCE did not impact 1,4-dioxane biodegradation one of the two soils. Lactate appeared to improve the initiation of the biological removal of cDCE in microcosms inoculated with either soil. Stable isotope probing (SIP) was then used to determine which phylotypes were actively involved in carbon uptake from cDCE and 1,4-dioxane in both soil communities. The most enriched phylotypes for 13C assimilation from 1,4-dioxane included Rhodopseudomonas and Rhodanobacter. Propane monooxygenase was predicted (by PICRUSt2) to be dominant in the 1,4-dioxane amended microbial communities and propane monooxygenase gene abundance values correlated with other enriched (but less abundant) phylotypes for 13C-1,4-dioxane assimilation. The dominant enriched phylotypes for 13C assimilation from cDCE included Bacteriovorax, Pseudomonas and Sphingomonas. In the cDCE amended soil microcosms, PICRUSt2 predicted the presence of DNA encoding glutathione S-transferase (a known cDCE upregulated enzyme). Overall, the work demonstrated concurrent removal of cDCE and 1,4-dioxane by indigenous soil microbial communities and the enhancement of cDCE removal by lactate. The data generated on the phylotypes responsible for carbon uptake (as determined by SIP) could be incorporated into diagnostic molecular methods for site characterization. The results suggest concurrent biodegradation of cDCE and 1,4-dioxane should be considered for chlorinated solvent site remediation.


Assuntos
Solo , Poluentes Químicos da Água , Biodegradação Ambiental , Dioxanos
15.
Acta Biomater ; 134: 261-275, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329786

RESUMO

Bioresorbable polymers composed of poly(D,L-lactide-co-glycolide) (PDLLGA) and poly(L-lactide-co-glycolide) (PLLGA) have become increasingly popular for the preparation of bone substitute constructs. However, there are reports of a delayed inflammatory reaction occurring months or years after implantation. Due to the long polymer degradation times, in vitro tests carried out at physiological temperature, 37°C, tend to assess only the short-term biocompatibility of these materials. The aim of this work is to develop an in vitro protocol that can be used to assess the long-term cytotoxicity of bioresorbable polymers in a time efficient manner. This study used a previously developed and validated accelerated degradation protocol to obtain samples of PDLLGA and PLLGA at increasing levels of degradation. Samples were then applied to standard ISO 10993-5 direct contact cytotoxicity testing and it was found that PDLLGA samples showed increasing levels of cytotoxicity at the later stages of degradation, with PLLGA samples demonstrating significantly less cytotoxic behaviour. Following concern that accumulation of acidic degradation products in a closed multi-well culture environment could overestimate cytotoxicity, we developed and validated a new dynamic flow culture methodology, for testing the cytotoxicity of these degradable materials, by adapting a commercial "organ on a chip" flow culture system, Quasi Vivo®. In addition to cytotoxicity testing, we have carried out profiling of inflammatory cytokines released by cells in response to degraded PDLLGA and PLLGA, and have suggested mechanism by which lactide-based bioresorbable materials could modulate the inflammatory response through the G-protein coupled receptor (GPCR), hydroxycarboxylic acid receptor 1 (HCA1). STATEMENT OF SIGNIFICANCE: Bioresorbable materials naturally disintegrate over time when implanted into the body. They are often used to make screws and clips for repair of broken bones. Unfortunately, some patients can react badly to the material, resulting in painful inflammation. Biomaterials scientists are interested in developing materials that are more compatible with the body. However, it is very difficult to predict the long-term compatibility of bioresorbable materials in the lab. In our study, we have developed a method that will allow us to study the effects of the materials as they continue to break down. This will help us understand why the materials may cause inflammation, and will support research into the development of new and improved materials for bone repair.


Assuntos
Implantes Absorvíveis , Ácido Poliglicólico , Materiais Biocompatíveis/toxicidade , Dioxanos , Humanos , Ácido Láctico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
16.
Pest Manag Sci ; 77(12): 5407-5417, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34314099

RESUMO

BACKGROUND: Botanical pesticides play an important role in organic agricultural practices and are widely used in integrated pest management (IPM). Uvaria grandiflora was mainly reported as traditional medicines and possessed antibacterial, antioxidant, and antiprotozoal activities. Therefore, important biological activities of U. grandiflora may suggest that they have the potential to be used as botanical pesticides. RESULTS: The extract of U. grandiflora exhibited broad-spectrum inhibitory activity toward phytopathogenic fungi and oomycetes, particularly against Colletotrichum musae and Phytophthora capsici, and its secondary metabolite zeylenone also displayed strong antifungal and anti-oomycete activities against phytopathogens. Particularly, half maximal effective concentration (EC50 ) values of zeylenone against Phytophthora capsici and C. musae were 6.98 and 3.37 µg mL-1 , showing better inhibitory effects than those of commercial fungicides (azoxystrobin and osthole). Additionally, the pot experiments showed that the extract of U. grandiflora could effectively control Pseudoperonospora cubensis, Phytophthora infestans, Phytophthora capsici and Podosphaera xanthii. In the field experiment, 5% microemulsion of U. grandiflora extract exhibited 79.72% efficacy against cucumber powdery mildew at 87.5 g ha-1 on the 14th day after two sprayings, which was better than that of 21.5% trifloxystrobin and 21.5% fluopyram SC at 200.9 g ha-1 . Surprisingly, 5% microemulsion of U. grandiflora extract could promote cucumber growth significantly. Furthermore, the action mechanism analysis indicated that zeylenone may damage the cytoderm and affect energy metabolism of Phytophthora capsici. CONCLUSION: It is the first time that the extract of U. grandiflora and zeylenone have been discovered leading to broad application prospects in the development as botanical fungicides. © 2021 Society of Chemical Industry.


Assuntos
Fungicidas Industriais , Phytophthora infestans , Uvaria , Ascomicetos , Colletotrichum , Cicloexanos , Dioxanos , Fungicidas Industriais/farmacologia , Doenças das Plantas
17.
J Mech Behav Biomed Mater ; 121: 104650, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34166872

RESUMO

The recent growth of polymer 3D-printing has brought innovation to the medical implant field. Implants with complex porous structures can be fabricated by printing to tune mechanical behavior and enable diffusion, consequently improving integration with tissues in the human body. Poly(L-lactide-co-ε-caprolactone) (PLCL) is a 3D-printable polymer that possess a wide range of possible mechanical properties depending on its monomer composition. It is often used in biomedical applications requiring degradability. In this study, we explore 1) the effect of annealing 3D-printed PLCL and 2) the degradation profile of both annealed and unannealed 3D-printed PLCL scaffolds. The degraded samples were characterized for its molecular weight, mass loss, microstructure, and mechanical properties. By annealing the 3D-printed PLCL, we reveal the structure-property relationship of PLCL. Crystallization was found to be a crucial factor in the resulting mechanical properties, increasing stiffness significantly. The subsequent degradation study revealed that there was no significant difference brought about by pre-annealing the scaffolds. The scaffolds were found to maintain their mechanical properties until up to 8 weeks, at which point the scaffolds reached a critical molecular weight and lost their mechanical integrity.


Assuntos
Poliésteres , Polímeros , Caproatos , Dioxanos , Humanos , Lactonas , Impressão Tridimensional , Engenharia Tecidual , Tecidos Suporte
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120086, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34161849

RESUMO

The pure rotational spectra of the 1:1 ethanol - 1,4-dioxane complex and its OD mono-deuterated species have been measured using pulsed-jet Fourier transform microwave spectroscopy. Conformational predictions for the plausible isomers of ethanol - 1,4-dioxane have been carried out considering the spatial orientation of gauche/trans ethanol with respect to the chair/boat and twisted conformations of 1,4-dioxane. Using Helium for the supersonic expansion, the microwave spectrum has been observed for the most stable structure. In the observed isomer, the two subunits are linked together by an OH⋯O hydrogen bond with gauche ethanol acting as proton donor to dioxane in the chair conformation. The non-covalent interactions have been characterized using different computational approaches. A small inverse Ubbelohde effect was observed after H â†’ D isotopic substitution in the OH⋯O hydrogen bond.


Assuntos
Dioxanos , Etanol , Modelos Moleculares , Conformação Molecular
19.
J Nat Med ; 75(4): 907-914, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34142303

RESUMO

Six dibenzo-1,4-dioxane derivatives (1-6) were isolated from the roots of a Hypericaceous plant Hypericum ascyron. Spectroscopic analyses revealed 2 and 4-6 to be new compounds. The partial racemic natures of 1-3 were concluded by chiral HPLC analyses, while 5 was confirmed to be a racemate. The absolute configurations 1-4 were deduced on the basis of ECD calculations. Biological activity evaluation of the dibenzo-1,4-dioxane derivatives along with two related compounds: hyperdioxanes A (7) and B (8), previously isolated from the same plant material by our group demonstrated that 7 exhibit an anti-HIV activity (IC50 5.3 µM, TI 7.2) while 8 showed an inhibitory effect on IL-1ß production (inhibition rate: 72.3% at 6.3 µM) from LPS-stimulated microglial cells.


Assuntos
Hypericum , Dioxanos , Estrutura Molecular , Raízes de Plantas
20.
J Hazard Mater ; 413: 125456, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33930970

RESUMO

The biotransformation of 1,4-dioxane, a endrocrine disrupting chemical was achieved using different bacterial strains and their consortia. Three different bacterial isolates were screened on their ability to grow with 50 mg/L 1,4-dioxane in the basal mineral medium. Then the isolates were tested for its efficiency to biotransform 1000 mg/L 1,4-dioxane at varying period of time; 24-120 h. The isolates were distinguished by their morphological features and 16 S rRNA gene sequencing was done to evaluate the phylogenetic relationships. The isolates were identified as Bacillus marisflavi strain MGA, Aeromonas hydrophila strain AG and Shewanella putrefaciens strain AG. The degree of biotransformation was escalated by constructing a bacterial consortium using statistical tool; response-mixture matrix under the design of experiments. The fully grown bacterial strains were used as ingredients in different proportions to formulate the consortium. The biotransformation was analyzed for functional attenuation using spectroscopic techniques and reduction in 1,4-dioxane level was confirmed using mass spectrometry. The precise quantification of biotransformation using mass spectral profile revealed that the consortium removed 31%, 61% and 85% of 1000 mg/L 1,4-dioxane within 96, 120 and 144 h respectively. The activities of inducible laccase were elucidated during biotransformation of 1,4-dioxane. Bio-toxicity of treated and untreated 1,4-dioxane on brine shrimp; Artemia salina showed that the biotransformed products were less toxic. Therefore, this report would be first of its kind to report the biotransformation and detoxification of 1,4-dioxane by a statistically designed bacterial consortium.


Assuntos
Bactérias , Bacillus , Bactérias/genética , Biotransformação , Dioxanos , Filogenia
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